In a semiconductor device to be mounted on a small and thin portable electronic device such as a cellular phone, the package area of the semiconductor device is narrow and the package height of the semiconductor device is small. Therefore, when a plurality of semiconductor chips are required to be mounted, the plurality of semiconductor chips are mounted on both surfaces of a single substrate to form a so-called double sided package semiconductor device. With the double sided package semiconductor device, the substrate would be made of resin or Si.
In the manufacture of the double sided package semiconductor device, first of all, a supporting substrate is prepared and the substrate is disposed on the supporting substrate, for example. Then, a predetermined wiring layer is formed on one surface of the substrate opposite to the supporting substrate and some semiconductor chips are formed on the wiring layer. Then, the supporting substrate is removed from the substrate and another wiring layer is formed on the other surface of the substrate to which the supporting substrate is attached so that the other semiconductor chips are additionally formed on another wiring layer. In this way, the intended double sided package semiconductor device can be manufactured.
The double sided package semiconductor device may be mounted on a mother board with external connecting circuits and external connecting terminals as occasion demands.
In the manufacture of the double sided package semiconductor device as described above, the supporting substrate can not be simply peeled off from the substrate by means of mechanical peeling because the thickness of the substrate is extremely thin up to about 10 μm. Therefore, various devices are implemented for the removal of the supporting substrate.